Charles James FoxPC (24 January 1749 – 13 September 1806), styled The Honourable from 1762, was a prominent British Whig statesman whose parliamentary career spanned 38 years of the late 18th and early 19th centuries and who was particularly noted for being the arch-rival of William Pitt the Younger. His father Henry, a leading Whig of his day, had similarly been the great rival of Pitt's famous father. Fox rose to prominence in the House of Commons as a forceful and eloquent speaker with a notorious and colourful private life, though his opinions were rather conservative and conventional. However, with the coming of the American War of Independence and the influence of the Whig Edmund Burke, Fox's opinions evolved into some of the most radical ever to be aired in the Parliament of his era.

Fox became a prominent and staunch opponent of George III, whom he regarded as an aspiring tyrant; he supported the American Patriots, even dressing in the colours of George Washington's army. Briefly serving as Britain's first Foreign Secretary in the ministry of the Marquess of Rockingham in 1782, he returned to the post in a coalition government with his old enemy Lord North in 1783. However, the King forced Fox and North out of government before the end of the year, replacing them with the twenty-four-year-old Pitt the Younger, and Fox spent the following twenty-two years facing Pitt and the government benches from across the Commons.

Though Fox had little interest in the actual exercise of power and spent almost the entirety of his political career in opposition, he became noted as an anti-slavery campaigner, a supporter of the French Revolution, and a leading parliamentary advocate of religious tolerance and individual liberty. His friendship with his mentor Burke and his parliamentary credibility were both casualties of Fox's support for France during the Revolutionary Wars, but he went on to attack Pitt's wartime legislation and to defend the liberty of religious minorities and political radicals. After Pitt's death in January 1806, Fox served briefly as Foreign Secretary in the 'Ministry of All the Talents' of William Grenville, before he died on 13 September 1806, aged fifty-seven.